blob: 5038c0789153d38ca9deccfa159157d096ee29eb [file] [log] [blame]
# Copyright 1999-2007 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2
import codecs
import os, re, sys
here_doc_re = re.compile(r'.*\s<<[-]?(\w+)$')
func_start_re = re.compile(r'^[-\w]+\s*\(\)\s*$')
func_end_re = re.compile(r'^\}$')
var_assign_re = re.compile(r'(^|^declare\s+-\S+\s+|^declare\s+|^export\s+)([^=\s]+)=("|\')?.*$')
close_quote_re = re.compile(r'(\\"|"|\')\s*$')
readonly_re = re.compile(r'^declare\s+-(\S*)r(\S*)\s+')
# declare without assignment
var_declare_re = re.compile(r'^declare(\s+-\S+)?\s+([^=\s]+)\s*$')
def have_end_quote(quote, line):
Check if the line has an end quote (useful for handling multi-line
quotes). This handles escaped double quotes that may occur at the
end of a line. The posix spec does not allow escaping of single
quotes inside of single quotes, so that case is not handled.
close_quote_match =
return close_quote_match is not None and \ == quote
def filter_declare_readonly_opt(line):
readonly_match = readonly_re.match(line)
if readonly_match is not None:
declare_opts = ''
for i in (1, 2):
group =
if group is not None:
declare_opts += group
if declare_opts:
line = 'declare -%s %s' % \
(declare_opts, line[readonly_match.end():])
line = 'declare ' + line[readonly_match.end():]
return line
def filter_bash_environment(pattern, file_in, file_out):
# Filter out any instances of the \1 character from variable values
# since this character multiplies each time that the environment
# is saved (strange bash behavior). This can eventually result in
# mysterious 'Argument list too long' errors from programs that have
# huge strings of \1 characters in their environment. See bug #222091.
here_doc_delim = None
in_func = None
multi_line_quote = None
multi_line_quote_filter = None
for line in file_in:
if multi_line_quote is not None:
if not multi_line_quote_filter:
file_out.write(line.replace("\1", ""))
if have_end_quote(multi_line_quote, line):
multi_line_quote = None
multi_line_quote_filter = None
if here_doc_delim is None and in_func is None:
var_assign_match = var_assign_re.match(line)
if var_assign_match is not None:
quote =
filter_this = pattern.match( \
is not None
# Exclude the start quote when searching for the end quote,
# to ensure that the start quote is not misidentified as the
# end quote (happens if there is a newline immediately after
# the start quote).
if quote is not None and not \
have_end_quote(quote, line[var_assign_match.end(2)+2:]):
multi_line_quote = quote
multi_line_quote_filter = filter_this
if not filter_this:
line = filter_declare_readonly_opt(line)
file_out.write(line.replace("\1", ""))
declare_match = var_declare_re.match(line)
if declare_match is not None:
# declare without assignment
filter_this = pattern.match( \
is not None
if not filter_this:
line = filter_declare_readonly_opt(line)
if here_doc_delim is not None:
if here_doc_delim.match(line):
here_doc_delim = None
here_doc = here_doc_re.match(line)
if here_doc is not None:
here_doc_delim = re.compile("^%s$" %
# Note: here-documents are handled before functions since otherwise
# it would be possible for the content of a here-document to be
# mistaken as the end of a function.
if in_func:
if func_end_re.match(line) is not None:
in_func = None
in_func = func_start_re.match(line)
if in_func is not None:
# This line is not recognized as part of a variable assignment,
# function definition, or here document, so just allow it to
# pass through.
if __name__ == "__main__":
description = "Filter out variable assignments for variable " + \
"names matching a given PATTERN " + \
"while leaving bash function definitions and here-documents " + \
"intact. The PATTERN is a space separated list of variable names" + \
" and it supports python regular expression syntax."
usage = "usage: %s PATTERN" % os.path.basename(sys.argv[0])
from optparse import OptionParser
parser = OptionParser(description=description, usage=usage)
options, args = parser.parse_args(sys.argv[1:])
if len(args) != 1:
parser.error("Missing required PATTERN argument.")
file_in = sys.stdin
file_out = sys.stdout
if sys.hexversion >= 0x3000000:
file_in = codecs.iterdecode(sys.stdin.buffer.raw,
'utf_8', errors='replace')
import io
file_out = io.TextIOWrapper(sys.stdout.buffer,
'utf_8', errors='backslashreplace')
var_pattern = args[0].split()
# Filter invalid variable names that are not supported by bash.
var_pattern = "^(%s)$" % "|".join(var_pattern)
re.compile(var_pattern), file_in, file_out)